Full Title: Effect of 4 weeks of high-intensity interval training on exercise performance and markers of inflammation and oxidative stress
Journal: The FASEB journal
Year of Publication: 2017
Mary Ann Lila
Publication Author(s): Kevin A Zwetsloot, David C Nieman, Amy Knab, Casey S John, Dominic D Lomiwes, Roger D Hurst, Nicolas D Gillitt, Mary A Lila
Prolonged, high intensity exercise induces substantial systemic inflammatory and oxidative stress responses. High intensity interval training (HIIT) involves bursts of heavy exertion separated by short rest periods; however, there is limited research on the effect of regular HIIT on the acute immune and oxidative stress responses to exercise. The purpose of this study was to determine the acute and chronic exercise-related physiological responses and adaptation to 4-weeks of cycling HIIT. We hypothesized that 4 weeks of HIIT would induce an attenuated inflammatory and oxidative stress response to an acute bout of HIIT. Sixty-one sedentary, but healthy participants (males: n=15, 21.8 ± 1.0 y, initial VO2max = 37.7 ± 1.7 ml•kg−1•min−1, body fat = 16.8 ± 1.6%; females: n=46, 20.2 ± 0.3 y, initial VO2max = 32.1 ± 0.7 ml•kg−1•min−1, body fat = 25.7 ± 0.8%) completed a maximal graded cycle ergometer test and an acute HIIT exercise bout (HIIT challenge) before and after 4 weeks of HIIT. The HIIT challenge was an acute bout of eight 60-sec cycling intervals at 100% of Wattsmax. The 4-week HIIT consisted of 12 sessions (3 d•wk−1) of 8 to 12 cycling intervals at 100% of Wattsmax (60-sec intervals; 75-sec rest in between). Standard exercise-related physiological variables were measured during the maximal cycle ergometer test and blood samples were collected at rest, immediately, and 30 min after completion of the HIIT challenge for analysis of inflammatory cytokines and markers of oxidative stress. Participants experienced 6% and 5% increases in VO2max and Wattsmax (both p≤0.001), respectively, after 4 weeks of HIIT. The post-exercise blood lactate response was lower after 4 weeks of HIIT (p=0.0125), compared to before training. We also observed reductions in exercise heart rate and rating of perceived exertion at various submaximal cycling workloads (all p≤0.001) after training. Plasma IL-6 increased immediately and 30 min after the HIIT challenge (p<0.0125), but 4 weeks of HIIT reduced this response (p<0.0125). IL-8 and MCP-1 increased in response to the HIIT challenge (both p≤0.001), but these responses were not altered by 4 weeks of HIIT. Before training, glutathione peroxidase (GPx) activity and malondialdehyde (MDA) levels increased (p=0.020 and p<0.001, respectively), but superoxide dismutase (SOD) activity was unchanged 30 min after the HIIT challenge. However, 4 weeks of HIIT further augmented GPx activity by 8% (p=0.026), attenuated MDA levels by 60% (p<0.001), and tended to increase SOD activity by 20% (p=0.059), in response to the HIIT challenge. In conclusion, 4 weeks of HIIT improves fitness and cycling exercise performance, and moderates the systemic inflammatory and oxidative stress responses to an acute bout of HIIT in sedentary men and women.
Link to Article: http://www.fasebj.org/doi/abs/10.1096/fasebj.31.1_supplement.839.1